Method of masking color transparencies



Nov. 14, 1944.. H. c. STAEHLE METHOD OF MASKING boLoR TRANSPARENCIES Filed March 20, 1941 TRANSPARENCY m m mm l.- mw CA HENRY- c. STAEHLE INVENTOR 0 BY L zgTORNEl s a method of masking col .parency and since a print- .while in contact with V Patented Nov. 14, 1944 METHOD OF MASKING COLOR SPARENCIES Henry C. Staehle, Rochester, N. Y.,,asslgnor to Eastman Kodak Company, Rochester, N. Y., a corporation 01' New Jersey Application March 20, 1941, Serial No. 384,389

7 Claims. (01. 154-40) of applya support rrection in us and particularly to or transparencies.

as been well established 01 separate plates and ed separately from the after processing, are re- This invention relates to a method ing an unexposed sensitive layer to and is particularlyuseful in color co masking color reproductio The art of masking 11 particularly by the use films which are process color transparency and, Fig. 1 is a sectional placed in register with the color transparency. oitransierring the se The chief objection to this procedure is that it to one ofapair of rolls, is difilcult to register the image produced in the Fig. 2 is a sectional masking plate or film with the image in the color of applying the sensitiv transparency, so that the definition oi. the reacolor transparency. sultingprintisimpaired. v y l. The masking film Methods have been devised for making the vention may be eith mask integral with the film with which it isto with emulsion and be used. For example, in Evans U. 8. Patent base side or a dry 2,203,653, granted June 4, 1940, a masking meth= able; dry stripping m d is described in which a gold negative mask is according to the pr formed in the layers 01' a multi-layer film durinvention is described ing color processing of the film. This procedure is not suitable with color transparencies which This film has the to have been prepared by the amateur or which thin layer of film su must be returned to a customer so that they may support of standard be' use'd forviewing. Another masking process ditions that the bond is described in Ehrenfried U. 8. Patent 2,203,652, is easily separated granted June 4, 1940. which involves the use of ing emulsion is coated a print-out emulsion which i temporarily bound constitutes the pe or cemented to a color transparency. The printing layer. A pan out la'yer isyex-posed through the color transout emulsion need not age is formed directly. eful inman cases, it hat print-out emulsions n practice and if the elelength of time,after exsion is preferabl To efifect the transi'e e d ve ped a masking .im

While this process is us has the disadvantage t are dimcult to handle i ment is kept for any portion consisting of 3 emulsion is separated These objects are accom In the accompanying tothe color transparency, the s port and as this is being done it one of a pair of smooth even r OFFICE plished by transferunprocessed photographic a thin support, to the color sing' it to light of suitable specthrough-the color transparency washing and drying it all color transparency. drawin l view showing the method nsitive stripping emulsion and view showing the method e stripping emulsion to in Nadeau and Starck U. S.

Patent 2,266,435, granted December 16, 1941.

llowing characteristics: A

pport iscoated on a film thickness under such conbetween the; two supports when dried. A suitable maskon the thin support which rmanent support for the maskchromatic or red-sensitive emuly used for the m asking layer.

original support tripping layer or ent Support and e temporary supis wound upon olls adjusted to r from the perman from th posure of the print-out emulsions. there is the ratherlight pressure. Soft rubber rolls are suitdanger .thatthe print-out layer will be tagged able for this purpose. When the entire trippin and the masking layer thereby rendereduseless. portion has been removed from It is, therefore, an tion to provide a m transparency which art'difilculties.

opposite direction and ing operations and will port and has been wound onto t transparency is passed between transparency or the base side film which is outermost. on th moistened with asuitable cemen base of the stripping film come the color transparency, a firm which will not loosen during sub its original supthe roll in the me time the color of the stripping e rubber roll is t. As soon as the s in contact with bond is effected sequent processany of the procat the sa not allow he roll. the color around the rolls but passes transparency has the following composition:

Gelatin grams 0.5 Acetic acid do 3 Water to ..-cc 100 Another suitable cement is one consisting of a dispersion of acrylic ester resin in water containing a wetting agen The masking emulsion may also be applied to the base side of the color transparency in. which cases this difluse mask applied to-the base has a distinct advantage over the mask applied tothe image side of the color transparency. In case the color transparency has a gelatin backing, the same cement may be used as is used for cementing the mask film to the image side of the color transparency.

The purpose and function of the masking layer as applied to color transparencies are well known. The purpose of the mask is first, to reduce the overall contrast of the color transparency and second, to increase the color saturation.

The contrast of the color transparency is reduced in that the mask is a low contrast negative of the original. It may be a positive mask applied to a color transparency negative or it may be a negative mask applied to a color transtransparency.

Color saturation is usually increased by using a. panchromatic or red-sensitive emulsion which is exposed through the colored original to red light. 'The exposure is, therefore, controlled almost entirely color transparency, assuming that the subtracthis color process is used. The result-is that a silver image is formed in the masking layer only over those layers which transmit red light freely and very little density is produced in the masking layer behind the blue, eye, or green areas. My invention will now ticular reference to the accompanying drawing which illustrates the preferred embodiment of the invention. As shown in Fig. 1, a stripping film comprising a temporary support ll of paper or cellulose ester having thereon a permanent support ll of suitable cellulose ester and panchromatic emulsion layer I2 is passed downwardly through soft rubber rolls i3 and i4 and the portion of the film comprising the permanent support and emulsion layer i2 is wound onto the roll M with theemulsion side in contact'with the roll. The temporary support It being relatively thick does not tendto" wrap between them leaving the sensitive portion of the stripping film on the roll I. This is readily accomplished by the use of a suitable dry stripping film such as that referred to above.

When the sensitive portion of the stripping film is entirely wound onto the roll ll, the color transparency is passed in the opposite direction be described with parcase a diffuse type mask is obtained. In some by the blue-green dye of the.

through the rolls as illustrated in Fig. 2 of the.

drawing. The color transparency may consist of a support It havingthereon layers l6, l1 and i8 containing colored images representing each of the three primary colors. It is obvious that a single-layer film or other type color transparency may also be used for receiving the masking layer.

, parency positive. In any case it produces a de- I sirable lowering of the contrast of the color Before the color transparency comes into contact with the masking film, the latteris coated with a suitable adhesive material, for example, by means of applicator rolls l9 and 20 which receive the adhesive from a reservoir 2i. The adhesive may also be applied by other suitable means to the support ll of the masking layer before it touches the color transparency. The pressure of the rolls l3 and It produces a firm even bond between the color transparency and the support ll of the masking film.

The mask described above may be used on any type color transparency such as motion picture film, out sheet film or glass plates. More than one mask may, of course, be applied to a color transparency either on one side or on both sides of the transparency. It is obvious that, in its broader aspects, this invention is capable of numerous applications whenever it is desirable or convenient to manufacture a photographic layer separately from the support to which it is to be permanently applied, and particularly where the permanent support is of glass or other rigid or frangible material not readily and cheaply transported. The examples and method described herein are illustrative only and it is to be understood that my invention is to be considered as limited only by the scope of the appended claims.

I claim:

1. The method of laminating a light-sensitive masking layer to a color transparency, which comprises wrapping a thin-base, light-sensitive photographic element on a cylindrical surface of 'one of a pair of rolls, passing the color transparency between the rolls in contact with the light-sensitive element, and cementing the lightsensitive element to the color transparency.

2. The method of laminating a light-sensitive layer to a rigid support, which comprises wrapping a thin-base, light-sensitive photographic element in one direction onto a resilient cylindrical surface to form a smooth coil of the element on the cylindrical surface and then transferring the photographic element in the opposite direction from the cylindrical surface onto a rigid plane surface on which it is to be exposed, and cementing the photographic element to the plane surface while pressing it into close contact with said plane surface by means of said resilient cylindrical surface.

3. The method of sensitizing a rigid sheet that comprises supplying a roll of flexible dry stripping material including a support and a portion including an unexposed photographic emulsion layer strippable therefrom while dry, stripping said portion from the support and applyingit to the sheet before exposure of said emulsion.

at the same time-supplying an adhesive between the sheet and portion and pressing them into close contact, whereby the unexposed photo'- graphic layer is securely attached to the sheet.

4. The method of sensitizing a rigid sheet that comprises supplying a roll of flexible dry stripping material including a support and a portion including an unexposed photographic emulsion layer, said portion being strippable from the 'support while dry. stripping said portion from the contact, the support being stripped in; dry state from said portion prior to exposure of the resulting sensitized sheet.

5. The method of laminating alight-sensitive including a permanent support, temporary support and sensitive emulsion layer, from said temmasking layer to a color transparency, which comprises transferring the light-sensitive element of a stripping iilm having a temporary 10 support from said temporary support to a oyline drical surface of one of a pair of rolls, passing the color transparency between the rolls in contact with the light-sensitive element, and cementing the light-sensitive element to the colortransparency with that surface of the light-sensitive element outermost which was originally outermost. i

6. The method of laminating a. light-sensitive masking layer to a color transparency. haying an emulsion on one side thereof, which comprises transferringthe light-sensitive emulsion layer and permanent support of a stripping mm porary support to a cylindrical surface of oneof a pair of rolls, passing the color transparency between the rolls with the emulsion side of said transparency in contact with said permanent support, and cementing the permanent support to the color transparency. w

7. The methodof laminating a light-sensitive masking layer to a color transparency, having an emulsion on one side thereof, which comprises transferring the light-sensitive emulsion layer and permanent support of a stripping fllm including a permanent support, temporary sup port and sensitive emulsion layer from said temporary support to a cylindrical surface of one of a pair of rolls, passing the color transparency between the rolls with the emulsion side of said transparency in contact. with said permanent ,support and cementing the permanent support to 1 the color transparency with a dilute solution of gelatin and acetic acid.

HENRY sraanm. 

